25 November, 2024

How do we view plants in the real world?


Are plants as advanced (> or =) as humans?


Plants pull all of this off while…


Plants as sessile organisms





  • Mostly defined by their total inability to move


  • Is this a good thing or a bad thing?


  • Their Darwinian struggle for growth, survival and reproduction in very different arenas has resulted in an extremely wide variety of form and function (Diaz et al 2016)

Themes in vascular plant form


  • Plants extract materials from environment
    • ~18 essential elements
      • soil (most)
      • atmosphere (a few)
    • these materials can be limiting


  • Above- and belowground body plan to extract resources
    • connected via vascular tissues

Themes in vascular plant form


  • Plants extract materials from environment
    • ~18 essential elements
    • soil (most)
    • atmosphere
    • many materials are limited


  • Above- and belowground body plan
    • connected via vascular tissues


  • Plants exhibit indeterminate growth
    • “foragers”
    • diversity of sizes & shapes

Diversity in plant form via resource uptake vs support

Diversity in plant form via evolutionary history

Derived traits on the plant phylogeny allowed plants to colonize most land surfaces

Diversity in plant form via environment (e.g., climate)

Plants adapt form to persist in different environments

Plants have 3 tissue systems connecting all plant organs

How do plants create such dynamic structures? Cells!

Parenchyma cells: living with metabolic function
















Parenchyma cells in leaves = Mesophyll cells Contain chloroplast and carry out photosynthesis

Collenchyma (flexible) & Sclerenchyma (rigid) for support

Vascular tissues: Xylem composed of water conducting cells


Vascular tissues: Phloem composed of sugar conducting cells


Dynamic root growth integral for plant function

Root morphology is super diverse

Roots are a member of a living soil community

Roots supply nutrients & water for growth & metabolism


Indeterminate growth occurs at meristems (tips)

Undifferentiated cells divide until they are ‘told’ what cells to turn into

Cambium produce secondary growth (out not up)

Vascular cambium creates new xlyem and phloem (tree rings) and cork cambium creates cork (bark)